The phrase of the song in debate is “This child that you’ve delivered, will soon deliver you”
It can be problematic for Catholics in the way you interpret the lyric. (let me emphasize the word interpretation)
If the phrase makes you believe that Jesus will be delivering Mary by forgiving her sin(s), well then of course, as a Catholic, how can you enjoy the song? We Catholics believe Mary was conceived with no sin at all.
However, you can interpret the phrase in many ways.
Here is how I interpret the phrase to my liking. (even if the person who wrote the song meant that Mary was delivered from sin, I’ll take my view over his intentions. If that’s the case, too bad for the writer I say. .……kind of like when the Church took a pagan feast like Halloween and turned it into All Souls/All Saints Day, not exactly the same analogy but close enough for me)
Mary had great faith, but she had to grow in her faith. In fact, even Jesus grew both in body and in wisdom; “without sin of course”. (see Luke 2:52) In Mary’s case, there were things that Mary didn’t fully understand. Example…
Mary was deeply troubled by the angel Gabriel’s greeting to her and she wondered what his words meant. (see Luke 1:29)
When the shepherds found Mary at Bethlehem and told her what the angel(s) had told them, Mary kept all these things, reflecting on them in her heart. (see Luke 2:19)
Again, when Joseph and Mary find the boy Jesus in the temple, they did not understand His answer. But again, Mary treasured all these things in her heart. (see Luke 2:50-52)
Now, you can believe that Mary was delivered when she fully understood everything.
Or, you can believe that she was delivered when she was assumed Body and Soul into Heaven.
But for me, I like to believe she was delivered at the foot of the cross when Jesus told her she was the Mother of us all. Jesus delivered Her to us. And just as she was happy to be the Mother of Jesus, she is happy to be the Mother of us also.